<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
   <ul id="oul_list">
       <li>121</li>
       <li>21321</li>
       <li>32213</li>
   </ul>
</body>
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   //
   //
   //  var obj ={
   //     firstName:'A',
   //     lastName:'B'
   //  }
   //  Object.defineProperty(obj,'fullName',{
   //      get:function () {
   //          return this.firstName + '-' + this.lastName
   //      },
   //      set:function (v) {
   //          const name = v.split('-');
   //          this.firstName =name[0];
   //          this.lastName = name[1]
   //      }
   //  })
   //  console.log(obj.fullName)
   //  obj.firstName = 'd'
   //  obj.lastName = 'e';
   // console.log(obj.fullName);
   // obj.fullName='ef-aa'
   // console.log(obj.firstName);
   // console.log(obj.lastName);

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</html>